Re: [PATCH v2 3/4] c++: Implement __remove_extent built-in trait

[Patrick Palka <ppalka@redhat.com>]

On Wed, 14 Feb 2024, Ken Matsui wrote:

> This patch implements built-in trait for std::remove_extent.
> 
> gcc/cp/ChangeLog:
> 
> 	* cp-trait.def: Define __remove_extent.
> 	* semantics.cc (finish_trait_type): Handle CPTK_REMOVE_EXTENT.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/ext/has-builtin-1.C: Test existence of __remove_extent.
> 	* g++.dg/ext/remove_extent.C: New test.

LGTM

> 
> Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
> ---
>  gcc/cp/cp-trait.def                      |  1 +
>  gcc/cp/semantics.cc                      |  5 +++++
>  gcc/testsuite/g++.dg/ext/has-builtin-1.C |  3 +++
>  gcc/testsuite/g++.dg/ext/remove_extent.C | 16 ++++++++++++++++
>  4 files changed, 25 insertions(+)
>  create mode 100644 gcc/testsuite/g++.dg/ext/remove_extent.C
> 
> diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
> index cec385ee501..3ff5611b60e 100644
> --- a/gcc/cp/cp-trait.def
> +++ b/gcc/cp/cp-trait.def
> @@ -96,6 +96,7 @@ DEFTRAIT_EXPR (REF_CONSTRUCTS_FROM_TEMPORARY, "__reference_constructs_from_tempo
>  DEFTRAIT_EXPR (REF_CONVERTS_FROM_TEMPORARY, "__reference_converts_from_temporary", 2)
>  DEFTRAIT_TYPE (REMOVE_CV, "__remove_cv", 1)
>  DEFTRAIT_TYPE (REMOVE_CVREF, "__remove_cvref", 1)
> +DEFTRAIT_TYPE (REMOVE_EXTENT, "__remove_extent", 1)
>  DEFTRAIT_TYPE (REMOVE_POINTER, "__remove_pointer", 1)
>  DEFTRAIT_TYPE (REMOVE_REFERENCE, "__remove_reference", 1)
>  DEFTRAIT_TYPE (TYPE_PACK_ELEMENT, "__type_pack_element", -1)
> diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
> index e23693ab57f..bf998377c88 100644
> --- a/gcc/cp/semantics.cc
> +++ b/gcc/cp/semantics.cc
> @@ -12777,6 +12777,11 @@ finish_trait_type (cp_trait_kind kind, tree type1, tree type2,
>  	type1 = TREE_TYPE (type1);
>        return cv_unqualified (type1);
>  
> +    case CPTK_REMOVE_EXTENT:
> +      if (TREE_CODE (type1) == ARRAY_TYPE)
> +	type1 = TREE_TYPE (type1);
> +      return type1;
> +
>      case CPTK_REMOVE_POINTER:
>        if (TYPE_PTR_P (type1))
>  	type1 = TREE_TYPE (type1);
> diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> index 56e8db7ac32..4f1094befb9 100644
> --- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> +++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
> @@ -170,6 +170,9 @@
>  #if !__has_builtin (__remove_cvref)
>  # error "__has_builtin (__remove_cvref) failed"
>  #endif
> +#if !__has_builtin (__remove_extent)
> +# error "__has_builtin (__remove_extent) failed"
> +#endif
>  #if !__has_builtin (__remove_pointer)
>  # error "__has_builtin (__remove_pointer) failed"
>  #endif
> diff --git a/gcc/testsuite/g++.dg/ext/remove_extent.C b/gcc/testsuite/g++.dg/ext/remove_extent.C
> new file mode 100644
> index 00000000000..6183aca5a48
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/ext/remove_extent.C
> @@ -0,0 +1,16 @@
> +// { dg-do compile { target c++11 } }
> +
> +#define SA(X) static_assert((X),#X)
> +
> +class ClassType { };
> +
> +SA(__is_same(__remove_extent(int), int));
> +SA(__is_same(__remove_extent(int[2]), int));
> +SA(__is_same(__remove_extent(int[2][3]), int[3]));
> +SA(__is_same(__remove_extent(int[][3]), int[3]));
> +SA(__is_same(__remove_extent(const int[2]), const int));
> +SA(__is_same(__remove_extent(ClassType), ClassType));
> +SA(__is_same(__remove_extent(ClassType[2]), ClassType));
> +SA(__is_same(__remove_extent(ClassType[2][3]), ClassType[3]));
> +SA(__is_same(__remove_extent(ClassType[][3]), ClassType[3]));
> +SA(__is_same(__remove_extent(const ClassType[2]), const ClassType));
> -- 
> 2.43.0
> 
>